fix(inputs.modbus): Handle field-measurement definitions correctly on duplicate field check (#12109)

plugins/inputs/modbus/configuration_request.go

@@ -110,7 +110,7 @@ func (c *ConfigurationPerRequest) Check() error {
 			def.Fields[fidx] = f
 
 			// Check for duplicate field definitions
-			id, err := c.fieldID(seed, def, f.Name)
+			id, err := c.fieldID(seed, def, f)
 			if err != nil {
 				return fmt.Errorf("cannot determine field id for %q: %v", f.Name, err)
 			}
@@ -253,7 +253,7 @@ func (c *ConfigurationPerRequest) newFieldFromDefinition(def requestFieldDefinit
 	return f, nil
 }
 
-func (c *ConfigurationPerRequest) fieldID(seed maphash.Seed, def requestDefinition, name string) (uint64, error) {
+func (c *ConfigurationPerRequest) fieldID(seed maphash.Seed, def requestDefinition, field requestFieldDefinition) (uint64, error) {
 	var mh maphash.Hash
 	mh.SetSeed(seed)
 
@@ -269,13 +269,13 @@ func (c *ConfigurationPerRequest) fieldID(seed maphash.Seed, def requestDefiniti
 	if err := mh.WriteByte(0); err != nil {
 		return 0, err
 	}
-	if _, err := mh.WriteString(def.Measurement); err != nil {
+	if _, err := mh.WriteString(field.Measurement); err != nil {
 		return 0, err
 	}
 	if err := mh.WriteByte(0); err != nil {
 		return 0, err
 	}
-	if _, err := mh.WriteString(name); err != nil {
+	if _, err := mh.WriteString(field.Name); err != nil {
 		return 0, err
 	}
 	if err := mh.WriteByte(0); err != nil {

plugins/inputs/modbus/modbus_test.go

@@ -2086,7 +2086,6 @@ func TestCases(t *testing.T) {
 		case 4: // 64-bit
 			binary.BigEndian.PutUint64(buf[1:], uint64(register))
 		}
-		fmt.Println(buf)
 		return buf, &mbserver.Success
 	}
 

plugins/inputs/modbus/testcases/duplicate_fields_issue_12091/expected.out

@@ -0,0 +1,7 @@
+Bitfield,name=EAP,resource=30KTL,slave_id=9,type=holding_register Alarm1=0u,Alarm2=0u,Alarm3=0u,State1=32000u,State2=0u,State3=0u
+Current,name=EAP,resource=30KTL,slave_id=9,type=holding_register PV1=0,PV2=0,PV3=0,PV4=0
+Power,name=EAP,resource=30KTL,slave_id=9,type=holding_register AC=32080,DC=32064,Efficiency=0
+Resistance,name=EAP,resource=30KTL,slave_id=9,type=holding_register Insulation=0
+Status,name=EAP,resource=30KTL,slave_id=9,type=holding_register Device=32086u
+Temp,name=EAP,resource=30KTL,slave_id=9,type=holding_register Internal=0
+Voltage,name=EAP,resource=30KTL,slave_id=9,type=holding_register PV1=0,PV2=0,PV3=0,PV4=0

plugins/inputs/modbus/testcases/duplicate_fields_issue_12091/telegraf.conf

@@ -0,0 +1,71 @@
+# Retrieve data from MODBUS slave devices
+[[inputs.modbus]]
+
+  # Hiermit wird auch _time auf 60s (also ganze Minuten) gerundet
+  # Sollten (nach der Timestamp Rundung) mehrere Abfragen auf denselben Timestamp (_time)
+  # kommen wird kein Fehler geworfen, sondern der bestehende Wert wird einfach upgedated!
+  precision = "60s"
+
+
+  ## Connection Configuration
+  ##
+  ## The plugin supports connections to PLCs via MODBUS/TCP, RTU over TCP, ASCII over TCP or
+  ## via serial line communication in binary (RTU) or readable (ASCII) encoding
+  ##
+  ## Device name
+  name = "EAP"
+
+  ## Timeout for each request
+  timeout = "500ms"
+
+  ## Maximum number of retries and the time to wait between retries
+  ## when a slave-device is busy.
+  busy_retries = 3
+  busy_retries_wait = "200ms"
+
+  # TCP - connect via Modbus/TCP
+  controller = "tcp://192.168.254.223:502"
+
+  ## Trace the connection to the modbus device as debug messages
+  ## Note: You have to enable telegraf's debug mode to see those messages!
+  debug_connection = true
+
+  ## Define the configuration schema
+  ##  |---register -- define fields per register type in the original style (only supports one slave ID)
+  ##  |---request  -- define fields on a requests base
+  configuration_type = "request"
+
+  ## --- "request" configuration style ---
+
+  ## Per request definition
+  ##
+
+  ## Define a request sent to the device
+  [[inputs.modbus.request]]
+    slave_id = 9
+    byte_order = "ABCD"
+    register = "holding"
+    fields = [
+      { address=32000, measurement="Bitfield", name="State1", type="UINT16" },
+      { address=32002, measurement="Bitfield", name="State2", type="UINT16" },
+      { address=32003, measurement="Bitfield", name="State3", type="UINT32" },
+      { address=32008, measurement="Bitfield", name="Alarm1", type="UINT16" },
+      { address=32009, measurement="Bitfield", name="Alarm2", type="UINT16" },
+      { address=32010, measurement="Bitfield", name="Alarm3", type="UINT16" },
+      { address=32016, measurement="Voltage", name="PV1", type="INT16", scale=0.1, output="FLOAT64" },
+      { address=32017, measurement="Current", name="PV1", type="INT16", scale=0.01, output="FLOAT64" },
+      { address=32018, measurement="Voltage", name="PV2", type="INT16", scale=0.1, output="FLOAT64" },
+      { address=32019, measurement="Current", name="PV2", type="INT16", scale=0.01, output="FLOAT64" },
+      { address=32020, measurement="Voltage", name="PV3", type="INT16", scale=0.1, output="FLOAT64" },
+      { address=32021, measurement="Current", name="PV3", type="INT16", scale=0.01, output="FLOAT64" },
+      { address=32022, measurement="Voltage", name="PV4", type="INT16", scale=0.1, output="FLOAT64" },
+      { address=32023, measurement="Current", name="PV4", type="INT16", scale=0.01, output="FLOAT64" },
+      { address=32064, measurement="Power", name="DC", type="INT32", output="FLOAT64" },
+      { address=32080, measurement="Power", name="AC", type="INT32", output="FLOAT64" },
+      { address=32086, measurement="Power", name="Efficiency", type="UINT16", scale=0.01, output="FLOAT64" },
+      { address=32087, measurement="Temp", name="Internal", type="INT16", scale=0.1, output="FLOAT64" },
+      { address=32088, measurement="Resistance", name="Insulation", type="UINT16", scale=0.001, output="FLOAT64" },
+      { address=32089, measurement="Status", name="Device", type="UINT16" },
+    ]
+    [inputs.modbus.request.tags]
+      resource = "30KTL"